UInt8
A 8 bit unsigned integer with values ranging from 0 to 255.
Extends
- {
"value":Field; }
Constructors
new UInt8()
new UInt8(x: number | bigint | FieldVar | UInt8): UInt8
Create a UInt8 from a bigint or number.
The max value of a UInt8 is 2^8 - 1 = 255.
Warning: Cannot overflow past 255, an error is thrown if the result is greater than 255.
Parameters
• x: number | bigint | FieldVar | UInt8
Returns
Overrides
Struct({
value: Field,
}).constructor
Source
Properties
value
value: Field = Field;
Inherited from
Struct({
value: Field,
}).value
Source
NUM_BITS
static NUM_BITS: number = 8;
Source
Unsafe
static Unsafe: {
"fromField": UInt8;
};
fromField()
Create a UInt8 from a Field without constraining its range.
Warning: This is unsafe, because it does not prove that the input Field actually fits in 8 bits.\ Only use this if you know what you are doing, otherwise use the safe UInt8.from.
Parameters
• x: Field
Returns
Source
_isStruct
static _isStruct: true;
Inherited from
Struct({
value: Field,
})._isStruct
Source
lib/provable/types/struct.ts:148
empty()
static empty: () => {
"value": Field;
};
Returns
{
"value": Field;
}
value
value: Field = Field;
Inherited from
Struct({
value: Field,
}).empty
Source
lib/provable/types/struct.ts:158
fromFields()
static fromFields: (fields: Field[]) => {
"value": Field;
};
Parameters
• fields: Field[]
Returns
{
"value": Field;
}
value
value: Field = Field;
Inherited from
Struct({
value: Field,
}).fromFields
Source
lib/provable/types/provable-intf.ts:115
fromJSON()
static fromJSON: (x: {
"value": Field;
}) => {
"value": Field;
};
Parameters
• x
• x.value: string= Field
Returns
{
"value": Field;
}
value
value: Field = Field;
Inherited from
Struct({
value: Field,
}).fromJSON
Source
lib/provable/types/struct.ts:157
fromValue
static fromValue: (x: {
"value": Field;
} | {
"value": Field;
}) => {
"value": Field;
} & (value: {
"value": Field;
}) => {
"value": Field;
};
Convert provable type from a normal JS type.
Inherited from
Struct({
value: Field,
}).fromValue
Source
lib/provable/types/provable-intf.ts:86
toAuxiliary()
static toAuxiliary: (value?: {
"value": Field;
}) => any[];
A function that takes value (optional), an element of type T, as argument and
returns an array of any type that make up the "auxiliary" (non-provable) data of value.
Parameters
• value?
the element of type T to generate the auxiliary data array from, optional.
If not provided, a default value for auxiliary data is returned.
• value.value?: Field= Field
Returns
any[]
Inherited from
Struct({
value: Field,
}).toAuxiliary
Source
lib/provable/types/provable-intf.ts:47
toCanonical()?
static optional toCanonical: (x: {
"value": Field;
}) => {
"value": Field;
};
Optional method which transforms a provable type into its canonical representation.
This is needed for types that have multiple representations of the same underlying value, and might even not have perfect completeness for some of those representations.
An example is the ForeignField class, which allows non-native field elements to exist in unreduced form.
The unreduced form is not perfectly complete, for example, addition of two unreduced field elements can cause a prover error.
Specific protocols need to be able to protect themselves against incomplete operations at all costs.
For example, when using actions and reducer, the reducer must be able to produce a proof regardless of the input action.
toCanonical() converts any input into a safe form and enables us to handle cases like this generically.
Note: For most types, this method is the identity function.
The identity function will also be used when the toCanonical() is not present on a type.
Parameters
• x
• x.value: Field= Field
Returns
{
"value": Field;
}
value
value: Field = Field;
Inherited from
Struct({
value: Field,
}).toCanonical
Source
lib/provable/types/provable-intf.ts:104
toFields()
static toFields: (value: {
"value": Field;
}) => Field[];
A function that takes value, an element of type T, as argument and returns
an array of Field elements that make up the provable data of value.
Parameters
• value
the element of type T to generate the Field array from.
• value.value: Field= Field
Returns
Field[]
Inherited from
Struct({
value: Field,
}).toFields
Source
lib/provable/types/provable-intf.ts:36
toJSON()
static toJSON: (x: {
"value": Field;
}) => {
"value": Field;
};
Parameters
• x
• x.value: Field= Field
Returns
{
"value": Field;
}
value
value: string = Field;
Inherited from
Struct({
value: Field,
}).toJSON
Source
lib/provable/types/struct.ts:156
toValue()
static toValue: (x: {
"value": Field;
}) => {
"value": Field;
};
Convert provable type to a normal JS type.
Parameters
• x
• x.value: Field= Field
Returns
{
"value": Field;
}
value
value: bigint = Field;
Inherited from
Struct({
value: Field,
}).toValue
Source
lib/provable/types/provable-intf.ts:81
Accessors
one
get static one(): UInt8
Static method to create a UInt8 with value 1.
Returns
Source
zero
get static zero(): UInt8
Static method to create a UInt8 with value 0.
Returns
Source
Methods
add()
add(y: number | bigint | UInt8): UInt8
Add a UInt8 to another UInt8 without allowing overflow.
Parameters
• y: number | bigint | UInt8
Returns
Example
const x = UInt8.from(3);
const sum = x.add(5);
sum.assertEquals(8);
Throws
if the result is greater than 255.
Source
assertEquals()
assertEquals(y: number | bigint | UInt8, message?: string): void
Assert that this UInt8 is equal another UInt8 value.
Important: If an assertion fails, the code throws an error.
Parameters
• y: number | bigint | UInt8
the UInt8 value to compare & assert with this UInt8.
• message?: string
Returns
void
Source
assertGreaterThan()
assertGreaterThan(y: number | bigint | UInt8, message?: string): void
Assert that this UInt8 is greater than another UInt8 value.
Important: If an assertion fails, the code throws an error.
Parameters
• y: number | bigint | UInt8
the UInt8 value to compare & assert with this UInt8.
• message?: string
Returns
void
Source
assertGreaterThanOrEqual()
assertGreaterThanOrEqual(y: UInt8, message?: string): void
Assert that this UInt8 is greater than or equal to another UInt8 value.
Important: If an assertion fails, the code throws an error.
Parameters
• y: UInt8
the UInt8 value to compare & assert with this UInt8.
• message?: string
Returns
void
Source
assertLessThan()
assertLessThan(y: number | bigint | UInt8, message?: string): void
Assert that this UInt8 is less than another UInt8 value.
Important: If an assertion fails, the code throws an error.
Parameters
• y: number | bigint | UInt8
the UInt8 value to compare & assert with this UInt8.
• message?: string
Returns
void
Source
assertLessThanOrEqual()
assertLessThanOrEqual(y: number | bigint | UInt8, message?: string): void
Assert that this UInt8 is less than or equal to another UInt8 value.
Important: If an assertion fails, the code throws an error.
Parameters
• y: number | bigint | UInt8
the UInt8 value to compare & assert with this UInt8.
• message?: string
Returns
void
Source
div()
div(y: number | bigint | UInt8): UInt8
Divide a UInt8 by another UInt8. This is integer division that rounds down.
Parameters
• y: number | bigint | UInt8
Returns
Example
const x = UInt8.from(7);
const quotient = x.div(2);
quotient.assertEquals(3);
Source
divMod()
divMod(y: number | bigint | UInt8): {
"quotient": UInt8;
"remainder": UInt8;
}
Get the quotient and remainder of a UInt8 divided by another UInt8:
x == y * q + r, where 0 <= r < y.
Parameters
• y: number | bigint | UInt8
a UInt8 to get the quotient and remainder of another UInt8.
Returns
{
"quotient": UInt8;
"remainder": UInt8;
}
The quotient q and remainder r.
quotient
quotient: UInt8;
remainder
remainder: UInt8;
Source
greaterThan()
greaterThan(y: number | bigint | UInt8): Bool
Check if this UInt8 is greater than another UInt8. Returns a Bool.
Parameters
• y: number | bigint | UInt8
Returns
Example
// 5 > 3
UInt8.from(5).greaterThan(3);
Source
greaterThanOrEqual()
greaterThanOrEqual(y: number | bigint | UInt8): Bool
Check if this UInt8 is greater than or equal another UInt8 value. Returns a Bool.
Parameters
• y: number | bigint | UInt8
Returns
Example
// 3 >= 3
UInt8.from(3).greaterThanOrEqual(3);
Source
lessThan()
lessThan(y: number | bigint | UInt8): Bool
Check if this UInt8 is less than another UInt8 value. Returns a Bool.
Parameters
• y: number | bigint | UInt8
Returns
Example
UInt8.from(2).lessThan(UInt8.from(3));
Source
lessThanOrEqual()
lessThanOrEqual(y: number | bigint | UInt8): Bool
Check if this UInt8 is less than or equal to another UInt8 value. Returns a Bool.
Parameters
• y: number | bigint | UInt8
Returns
Example
UInt8.from(3).lessThanOrEqual(UInt8.from(5));
Source
mod()
mod(y: number | bigint | UInt8): UInt8
Get the remainder a UInt8 of division of another UInt8.
Parameters
• y: number | bigint | UInt8
Returns
Example
const x = UInt8.from(50);
const mod = x.mod(30);
mod.assertEquals(20);
Source
mul()
mul(y: number | bigint | UInt8): UInt8
Multiply a UInt8 by another UInt8 without allowing overflow.
Parameters
• y: number | bigint | UInt8
Returns
Example
const x = UInt8.from(3);
const product = x.mul(5);
product.assertEquals(15);
Throws
if the result is greater than 255.
Source
sub()
sub(y: number | bigint | UInt8): UInt8
Subtract a UInt8 from another UInt8 without allowing underflow.
Parameters
• y: number | bigint | UInt8
Returns
Example
const x = UInt8.from(8);
const difference = x.sub(5);
difference.assertEquals(3);
Throws
if the result is less than 0.
Source
toBigInt()
toBigInt(): bigint
Serialize the UInt8 to a bigint.
Warning: This operation is not provable.
Returns
bigint
Source
toNumber()
toNumber(): number
Serialize the UInt8 to a number.
Warning: This operation is not provable.
Returns
number
Source
toString()
toString(): string
Serialize the UInt8 to a string, e.g. for printing.
Warning: This operation is not provable.
Returns
string
Source
toUInt32()
toUInt32(): UInt32
Returns
Source
toUInt64()
toUInt64(): UInt64
Returns
Source
MAXINT()
static MAXINT(): UInt8
Creates a UInt8 with a value of 255.
Returns
Source
check()
static check(x: Field | {
"value": Field;
}): void
Provable.check for UInt8. Proves that the input is in the [0, 255] range.
Parameters
• x: Field | {
"value": Field;
}
Returns
void
Overrides
Struct({
value: Field,
}).check
Source
from()
static from(x:
| number
| bigint
| Field
| UInt64
| UInt32
| UInt8): UInt8
Creates a new UInt8.
Parameters
• x:
| number
| bigint
| Field
| UInt64
| UInt32
| UInt8
Returns
Source
sizeInFields()
static sizeInFields(): number
Return the size of the T type in terms of Field type, as Field is the primitive type.
Returns
number
A number representing the size of the T type in terms of Field type.
Inherited from
Struct({
value: Field,
}).sizeInFields
Source
lib/provable/types/provable-intf.ts:66
toInput()
static toInput(x: {
"value": Field;
}): HashInput
Parameters
• x
• x.value: Field
Returns
HashInput
Overrides
Struct({
value: Field,
}).toInput